The capacity for neurogenesis in the adult mammalian brain is extremely limited and highly restricted to a few regions, which greatly hampers neuronal regeneration and functional restoration after neuronal loss caused by injury or disease. Meanwhile, transplantation of exogenous neuronal stem cells into the brain encounters several serious issues including immune rejection and the risk of tumorigenesis. Recent discoveries of direct reprogramming of endogenous glial cells into functional neurons have provided new opportunities for adult neuro-regeneration. Here, we extensively review the experimental findings of the direct conversion of glial cells to neurons in vitro and in vivo and discuss the remaining issues and challenges related to the glial subtypes and the specificity and efficiency of direct cell-reprograming, as well as the influence of the microenvironment. Although in situ glial cell reprogramming offers great potential for neuronal repair in the injured or diseased brain, it still needs a large amount of research to pave the way to therapeutic application.

成年哺乳动物大脑的神经发生能力极其有限，并且高度局限于少数几个区域，这极大地阻碍了因损伤或疾病引起的神经元丧失后的神经元再生和功能恢复。同时，将外源性神经元干细胞移植到大脑中会遇到一些严重的问题，包括免疫排斥和肿瘤发生的风险。最近发现内源性神经胶质细胞直接重编程为功能性神经元，为成人神经再生提供了新的机会。在这里，我们广泛回顾了神经胶质细胞在体外和体内直接转化为神经元的实验结果。并讨论与神经胶质亚型和直接细胞重编程的特异性和效率相关的剩余问题和挑战，以及微环境的影响。尽管原位神经胶质细胞重编程为受损或患病大脑的神经元修复提供了巨大潜力，但仍需要大量研究为治疗应用铺平道路。